Gripper mechanism.



A. BATES.

GRIPPEB. MECHANISM.

APPLICATION FILED JAN. 2. 191a.

' 1,079,590, Patented Nov. 25, 1913.

ED STATES PATENT orruon.

ENGLAND, ASSIGNOR T0 UNITED SHOE MACHINERY NEW JERSEY, A CORPORATION OF NEW JERSEY.

GRIPPER MEQHANISM.

amaseo.

Specificatipn of Letters Patent. I

Patented Nov. 25, 1913.

Application filed January-2, 1913. Serial No. 739,701.

To all whom it may concern:

Be it known that I,'ARTHUR BATns, a subject of the King of England, and resident of Leicester, Leicestershire, England, have invented certain Improvements in Gripper Mechanisms, of which the following description, in connection with the'accompanying drawings, is a specificatiomlike reference characters on the drawings indicating like parts in the several figures.

This invent-ion relates to pulling over or like machines and is an improvement in or modification of the invention described in the specification of prior United States Letters Patent No. 1,030,522, granted June 25, 1912 on application of Ronald F. Mclfeely and an ob ect of the present invention is to improve the construction and operation of the gripper mechanism of the machine therein shown.

The machine of the priorpatent is provided with a pair or set of grippers at each side of the shoe and also with acompensatmg or equalizing device for each air of grippers that permits each gripper o" a pair to move during the closing movement or during the updraw movement of the grippers or during both the updraw and closing movement, relatively to the other gripper of the pair. This enables the two grippers to be closed to different extents in order to accommodate the varying thickness of stock at different portions of the edge of the upper, such for example as the portion of the upper adjacent to the toe cap, or to allow the two grippers unequal range of movement for equalizing the tension in order to provide for different amounts of stretching of the upper. In practice the equalizing or compensating device of said prior construction 's, in iny opinion, open to the further criticism that when used upon, certain work, as for example with lasts having high or prominent toes the range of relative movement of the two- This arrangement has been found in practice to be dlsa vantageous in view of the fact that the various other mechanisms connected to the gripper jaws are by necessity situated in this part of the chamber so that the range of relative or equalizing movement that could be imparted to the grippers was undesirably limited and difficulty occurred when it was necessary to inspect the said device or toremove and replace it. Consequently in accordance with a feature of this invention the gripper compensating or equalizing device is situated at a point considerably nearerthe top of the updraw bar and within easy reach of the operator for removal, inspection or other purposes An important feature of this invention consists in a gripper'mechanism comprising two adjacent single operating bar having one or more pinions the nected respectively with said pairs of-jaws. Preferably there are separate latches- 'bywhich the two pairs ofjaws have detachable engagement with their closing mechanism.

opposite sides of which are congrippers or pairs of jaws and a chine having a gripper mechanism comprising two adjacent grippers and a single bar for operating them there is provided between each gripper and the said bar a connector having rack teeth. and there is also provided a pinion or pinions mountedu'pon the said bar preferably at a point well above the jaw closing mechanisms and accessible to the operator and engaging the said rack teeth, thus roviding the gripper mechanism with a difl rential device whereby the two grippers may move relatively to one another to put different portions of the upper acted upon under the same strain. It will be noted that when the gripper-operating baris updrawn the pinion will also be updr'awn and both connectors will move upward together and the jaws will close upon the work to pull it. ,If the stress upon the two grippers 1 18 equal they will not move relatively but if the stress is not equal there will be relative movement until anequality occurs and during this relative movement the pinion will rotate in such a manner that it tends to decrease the stress upon the one gripper and to correspondingly increase the stress upon the other gripper. It will thus be seen that each connector operates in the opening and closing of its gripper and also in the pulling movement independently of the other except that the speed and the extent of the movement of each is relatively appropriate to the part of the work upon which it is operating. Preferably the differential Compensating device is so arranged with reference to the grippers that its operation will not affect the force of the grip of the grippers. The features of the invention above indicated, together with the novel combinations of parts and details of construction disclosed in the accompanying drawings will more fully appear in connection with the following'description of the illustrated embodiment of the invention and will then be pointed out in the claims.

In order that the present invention may be more readily understood the gripper mechanism with its equalizing device as constructed according to the prior invention has first been shortly described, and hereafter the preferred construction of gripper mechanism and equalizing device according to thepresent invention will be described with reference to the accompanying drawings but it is to be understood that the invention is not to be considered as limited to the precise construct-ion set-forth.

In the drawings :Figure 1 is a side elevation of so much of a pulling-over machine as is necessary to show the embodiment of the present invention in one of its side gripper mechanisms; Fig. 2 is a vertical transverse section of the forward gripper member of a pair; Fig. 3 shows a horizontal cross section of the side gripper mechanism takenon the line 3-3 of Fig. 1; Fig. 4 shows a similar cross sect-ion on the line 4-4 of Fig. 1. 4 1

An operating bar 168 supports a gripper carrier comprising two blocks 25, 26 which are grooved longitudinally and placed to gether in'such a manner as to form along chamber, U-shaped in cross section, Fig. 4, the open side of the chamber being closed by two cover plates 27, 28 secured tothe blocks by screws. The block 26 has firmly secured to it the usual fixed gripper jaw 29, a movable jaw 30 being pivoted to the block at 31 and being provided with a tongue adapted to be engaged by a roll 32 mounted on the looseslid'e 33 which is normally moved to its lowest position by means of its own weight so that the roll 32'is normally inoperative to close the gripper jaws. The slide 33 has formed on it 3. lug 34 which is engaged at certain times by a latch 35 which is pivoted to the lower end of a,vertically movable slide or connector 36 and is turned toward the lug by a spring pressed plunger as shown in dotted lines in Fig. 2 to enable the latch 35 to be disengaged from the lug 34.

The tripper 204 before mentioned is pivoted at one end to the loose slide 33. By pressing upon the loose end of the tripper an ear upon it is causedto force the latch 35 from under the lug 34 and allow the slide 33 to descend and open the jaws. In order that there may be relative movement between the connector 36 and the gripper casing the connector is recessed upon one side and a sprin' 38 is provided which bears at one en against the top of the recess and at the other end against a cross piece 39 riveted to the block 26 of the gripper casing. The spring thus serves to hold the-gripper casing in its lowest position which is determined by a ledge 40 which projects from the lower end of the connector 36 underneath the cross piece 39 as shown in Figs. 1 and 2. When the power actuated lever 2 is in its lowest position the spring 38 is fullycompressed and the connector 36 and latch 35 are so low that the latch is pressed by its spring plunger into position underneath the lug 34, the loose slide 33 being then at the lowest limit .of its movement. As the operating lever 2 rises it pulls up the bar 168 and also the connector 36' so that the latch hooks under the lug 34 and thereby raises the slide 33 thus causing the roll 32 to operate upon and close the jaw 30. After the jaw has been closed further upward movement of the latch 35 lifts the jaw and the block 26 because the roll 32 is unable to move upward relatively to the tail of the jaw 30 and therefore the, grippers not only close upon the upper but are thereafter lifted to stretch the upper by the continued movement of the lever 2 in the same direction upward.

The description-thus far has related to one pair of the side gripper jaws shown in Fig. 1 or to one gripper, as will be expressed in some of the clalms for convenience in designation of the mechanism, and it will be understood that the construction and operation of the other pair of jaws, or gripper, as for example the left hand pair, is identical with that of the right hand pair and that there are, in fact, two separate connectors 36, as is plainly shown in Fig. 1, which are connected with the gripper operating bar 168 by a compensating and equalizing device constructed and arranged as follows: The upper portion of each of the connectors 36 is provided with teeth 42 that are arranged so as to face one another and leave a space between them, Figs. 1 and 3. Within gripper operating bar 168 will be transmitted through the pinions and toothed connectors 36 to the loose slides 33 that operate to close and uplift the grippers so that in the event of different thicknesses of stock being gripped or in the event of the difierent parts of the upper seized by the right and left pairs of jaws, Fig. 1, stretching to different extents, said connectors and pinions will permit the grippers to-be'closed to the required different degrees and also will allow different amounts of updraw movement to be imparted to the right and leftpairs of grippers to correspond with the variation" in the stretch of the upper. The advantage of this equalizing or compensating device is two-fold, since it not only permits a greater range of relative movement of the grippers, but also allows, when the tension on one gripper exceeds that on the other, the second gripper to move at a quicker rate than the operating bar 168 so that the tension on the upper is very quickly equalized. Further, it will be noticed that the o eration of the equalizing device does not a ect the degree of compression of the spring 38 so that the limit of the grip of the jaws upon the work is not afi'ected by the relative position of the two pairs of .jaws.

Having described my invention, What I claim and desire to secure by Letters Patent of the United States is: K

1. A machine of the class described having, in combination, with suitable operating mechanism, a gripper mechanism comprising two adjacent grippers and a single bar for operating them, a connector located between each gripper and the said bar and havingrack teeth, and a pinion carried by the said bar and engaging the said rack teethwhereby the grippers are moved to do their work and also'may move relatively to one another for the purpose specified.

2. In a machine of the class described, a gripper mechanism comprising two adjacent grippers having rack toothed bars connected therewith, a single operating bar, and an equalizing pinion through which and said toothed bars the operating bar is connected to the two grippers.

3. In a machine of the class described, a gripper mechanism comprising two adjacent grippers each having a separate connector bar 36 provided with rack teeth on its face adjacent to the companion bar, and a single operating bar provided between saidconnecting bars with two pinions both engaging the racks thereon.

4. In a gripper mechanism for pulling an upper over a last, a plurality of pairs of jaws for engaging the upper of the same side of a shoe, se arate closing mechanisms for said airs o jawsincluding separate latches 20 each of which has detachable engagement with a closing mechanism, a single operating means for biting the jaws, and equalizing means whereby the several pairs of jaws are caused to put different portions of upper acted upon under the same strain.

5. In a gripper mechanism for ulling an upper over a last, a plurality 0 pairs of jaws for engaging the upper of the same side of a 'shoe, separate closing mechanisms for said pairs of jaws, a single operating bar for lifting the jaws, separate connectors extending from the jaws to said operating bar, and rack and pinion equalizing means between said bar and said connectors.

6. In a gripper mechanism for ulling an upper over a last, a plurality 0 pairs of jaws for engaging the upper of the same side ofv a shoe, separate closing mechanisms for said pairs of jaws, a single operating bar for lifting the jaws, separate connectors extending from the jaws to said operating bar, and equalizing connections arranged between the separate connectors and the operating bar and located above and separate from the said closing mechanisms.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

ARTHUR BATES.

Witnesses:

FREDERICK WILLIAM WORTH, THOMAS ALBERT HOUGH. 

